1. Field of the Invention
The invention relates to a system and method for monitoring environmental conditions, such as temperature and humidity, inside granulated piles, at production and storage sites. Even though the present invention relates primarily to use in granulated fertilizer piles, it is not limited to such use.
2. Description of Related Art
Temperature and humidity monitoring systems are known in the art. However, in the phosphate fertilizer industry, samples from granulated phosphate fertilizer piles containing Granulated Triple Super-Phosphate (GTSP), Mono-Ammonium Phosphate (MAP), or Di-Ammonium Phosphate (DAP) may have to be sent to a lab after a moisture related problem occurs, to determine corrective dust control measures and measures to overcome humidity problems associated with the locations where the piles are located. For example, changes in the granulation process may be required, including modifying the dust control measures. A problem associated with the current practice, is that there is uncertainty and delay in assessing when a pile is ready to load, that is aged, or which pile might show signs of pile set. A pile is aged when a soluble phosphate level in the pile reaches 46 percent. Should a pile set, that is, cease its aging process, a significant amount of production and loading time is lost.
Humidity can cause significant caking of the piles of granulated fertilizer on ships, in warehouses and in mines. A cap is formed on the top of the pile ranging from 2 inches thick to about 2 feet thick. The cap turns white and poses significant dust problems. Should a fertilizer pile cake up, in order to unload or load the pile, blasting sometimes has to be resorted to, subjecting companies to liability for property damage or injury to personnel.
Known related art includes a soil profile probe depicted in U.S. Pat. No. 4,445,788 to Twersky et al., a temperature and humidity surveillance system for use in steam power plants depicted in U.S. Pat. No. 4,553,432 to Barlian et al., and a humidity monitoring system for grain silos depicted in U.S. Pat. No. 2,834,201 to Ohlheiser.
Other known related art include U.S. Pat. No. 3,459,925 to Goosey et al., U.S. Pat. No. 3,938,385 to Horwath, U.S. Pat. No. 3,982,110 to Kawai, U.S. Pat. No. 4,114,442 to Pratt, U.S. Pat. No. 4,176,554 to Kazmierowicz, U.S. Pat. No. 4,324,138 to Davis et al., U.S. Pat. No. 4,408,904 to Tokarz, U.S. Pat. No. 4,412,090 to Kawate et al., U.S. Pat. No. 4,707,148 to Richmond, U.S. Pat. No. 4,483,631 to Kydd, U.S. Pat. No. 5,025,248 to Bergeron, and U.S. Pat. No. 5,217,306 to Wada.
None of the devices in the above references solve the problem of providing on-site field data and correlation of the temperature and humidity or other environmental conditions, such as pressure, inside phosphate fertilizer piles or similar granulated pile materials at specific production sites such as in mines, in warehouses or in ships such that operators can monitor the aging of the pile until it reaches grade, generally 46 percent soluble phosphate level, or such that operators can take timely measures to change the granulation process, if necessary, and/or to evaluate the effects of dust control measures or to provide additional dust control measures. An object of the present invention would provide an easily assembled or preassembled environmental condition monitoring system and method of use such that the part of the system housing the detectors can be readily placed in a pile of granulated fertilizer in a desired or predetermined orientation within the pile. The invention would provide on-site field data by monitoring and evaluating parameters, such as temperature and humidity, inside a pile of granulated fertilizer such that the effects of dust control measures can be evaluated and changes in the granulation process can be considered based on the environmental conditions within the pile as the pile is aging until it reaches grade, thereby saving production costs.